Figure 7
Thermal Chimney Effect Built into Home
Inlets close to a wall result in air “washing” along the wall. Be certain to have centrally located inlets for air movement in the center areas of the room.
Window insect screens decrease the velocity of slow breezes more than stronger breezes (60% decrease at 1.5 mph, 28% decrease at 6 mph). Screening a porch will not reduce air speeds as much as screening the windows.
Night ventilation of a home should be done at a ventilation rate of 30 air changes per hour or greater. Mechanical ventilation will usually be required to achieve this (See Fan Section).
High mass houses can be cooled with night ventilation providing that fabric furnishings are minimized in the house.
Keep a high mass house closed during the day and opened at night.